title: Communication: Singularity-free hybrid functional with a Gaussian-attenuating exact exchange in a plane-wave basis.
abstract: Integrable singularity in the exact exchange calculations in hybrid functionals is an old and well-known problem in plane-wave basis. Recently, we developed a hybrid functional named Gaussian-attenuating Perdew-Burke-Ernzerhof (Gau-PBE), which uses a Gaussian function as a modified Coulomb potential for the exact exchange. We found that the modified Coulomb potential of Gaussian function enables the exact exchange calculation in plane-wave basis to be singularity-free and, as a result, the Gau-PBE functional shows faster energy convergence on k and q grids for the exact exchange calculations. Also, a tight comparison (same k and q meshes) between Gau-PBE and two other hybrid functionals, i.e., PBE0 and HSE06, indicates Gau-PBE functional as the least computational time consuming. The Gau-PBE functional employed in conjunction with a plane wave basis provides bandgaps with higher accuracy than the PBE0 and HSE06 in agreement with bandgaps previously calculated using Gaussian-type-orbitals.
authors.affiliation: Computational Chemistry Unit, RIKEN Advanced Institute for Computational Science, 7-1-26, Minatojima-minami-machi, Chuo-ku, Kobe, Hyogo 650-0047, Japan.
authors.forename: Jong-Won
authors.initials: JW
authors.lastname: Song
authors.forename: Giacomo
authors.initials: G
authors.lastname: Giorgi
authors.forename: Koichi
authors.initials: K
authors.lastname: Yamashita
authors.forename: Kimihiko
authors.initials: K
authors.lastname: Hirao